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The ChemCollective >> Stoichiometry Tutorials>> The Mole

Stoichiometry Tutorials: Part 1 - The Mole (from a complete OLI stoichiometry course)

You probably remember the mole from high school chemistry, but do you remember why it is useful to chemists? The goal of the following video is to give the "big picture" of the mole and its applications; information on how to use the mole in calculations can be found in another tutorial.

Throughout this course, we will use the term "molecular weight" to refer to the mass of a mole of a substance (for instance, the molecular weight of oxygen (O2) is 32 g/mol). Recent textbooks refer to this as "molar mass" to emphasize (i) that this term refers to the mass, not the weight, of substance, and (ii) that the quantity refers to a mole of a substance, not a single molecule. "Molecular weight" may be less precise, but it remains the term that most practicing chemists use in the laboratory. For this reason, we continue to use "molecular weight" in this course.

Text version of this movie.

Below you will find some practice questions to get you used to the concepts and calculations concerning the Mole.

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   Page Last Updated: 02.15.2011